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Next story in Somalia

NAIROBI, Kenya — Somali pirates hijacked three vessels in less than two days, diplomats and officials said Monday, with the pattern of attacks suggesting the pirates are trying to evade warships patrolling the Gulf of Aden.

The Taiwanese ship Win Far 161 was seized early Monday near an island in the Seychelles in the Indian Ocean, said Lt. Nathan Christensen, a spokesman for America's Bahrain-based 5th Fleet.

The 30 crew comprised 17 Filipinos, six Indonesians, five Chinese and two Taiwanese, according to a Taiwan Foreign Minister statement. It was the second attack in the Seychelles within a week.

A small Yemeni boat was also hijacked in the Indian Ocean Sunday and a 35,000-ton British-owned bulk carrier, the Malaspina Castle, was hijacked early Monday in the Gulf of Aden, officials said.

Latest in series of attacks
The hijacking of the Taiwanese vessel and Yemeni boat are the latest in a series of attacks in the Indian Ocean. A 20,000-ton German container ship, the Hansa Stavanger, was also seized there on Saturday.

Analysts say the pirates have moved many of their operations out of the Gulf of Aden, which is heavily patrolled by naval warships from countries including China, the United States, France and India.

Instead, they are targeting ships coming out of the Mozambique Channel, an area of the Indian Ocean further south between the southeastern Africa coast and Madagascar.

The Brussels-based European anti-piracy force said the Malaspina Castle was carrying iron and had 24 people on board from Bulgaria, the Philippines, Russia and Ukraine.

Lloyd's Marine Intelligence Unit said the ship was managed by BNavi SpA of Italy and owned by Navalmar U.K. Ltd. A Nairobi-based diplomat said the ship flies a Panamanian flag.

The Yemeni boat had seven crew on board when it was hijacked, an official with Yemen's Interior Ministry said Monday. Authorities received a distress call from the captain saying his boat was being hijacked in the Indian Ocean on Sunday, the official said.

The diplomats and officials spoke on condition of anonymity because they were not authorized to speak to the media.

Boats used as 'mother ships'Although small boats like the Yemeni fishing vessel do not fetch large ransoms, the pirates often use such boats as 'mother ships', which tow the small speedboats the prates use hundreds of miles out to sea. The mother ships also hold fuel and food for the pirates while they wait to attack more valuable vessels.

The multimillion-dollar ransoms from large ships with valuable cargos are a rare source of cash in Somalia, where nearly half the population is dependent on food aid and clan-based militias are tearing the country apart. The lawless Horn of Africa nation has not had a functioning government since 1991.